KIPS Rack Friction

[exbike]

I'm rebuilding my KDX's KIPS system. Recently I had the cylinder replated which, during the process, included a sandblasting/chemical stripping of the entire cylinder. My question involves the relative friction or ease that the KIPS valve engages. I am worried that there is excess friction in the right side rack (sitting on bike) - the one that has an o-ring type seal on it. I am thinking that the newly roughened surface in the right side's rack well is now creating quite a bit of friction where it interfaces the rack's o-ring. This, in turn, seems to be causing a little excess friction for the entire KIPS system.

So the non-scientific, subjective question is this: should it take much effort to open and close the KIPS system when you operate it by rolling the right side actuator cog with your fingers? My moves well, but it just takes a bit to get the system moving.

Thanks! -Matt

 

[karlp]

I had exactly the same experience and effect, but did not ask the question. I put it back together anyway, hoping for the best
Now my bike's KIPS opens abruptly, late, and is slow to close.
I doesn't bother me a whole lot, however....
If I could do it all over again I'd have cussed out the guys that did the replating for not sealing off that bore before doing whatever they did to it, and I'd have figured out some way to smooth it out so the KIPS operated smoothly.

I don't know what I would have done. Maybe some emery cloth wrapped around a drill bit and ream it out untill the right side rod slides smooth?

Let me know what works. I have a ring/piston replacement coming in the not to distant future and I'll want to try to fix what the platers did


Karl

 

[exbike]

Thanks for the reply Karl - I thought I was losing my mind. Thanks for sharing your experience with this.

Your suggestion of the emory paper/drill bit sounds like a very good plan. After I'm done I'll let you know if I was able to get the rack's bore smooth enough for an overall reduction in friction.

Take care, Matt

 

[droopie69]

I'm rebuilding my KDX's KIPS system. Recently I had the cylinder replated which, during the process, included a sandblasting/chemical stripping of the entire cylinder. My question involves the relative friction or ease that the KIPS valve engages. I am worried that there is excess friction in the right side rack (sitting on bike) - the one that has an o-ring type seal on it. I am thinking that the newly roughened surface in the right side's rack well is now creating quite a bit of friction where it interfaces the rack's o-ring. This, in turn, seems to be causing a little excess friction for the entire KIPS system.

So the non-scientific, subjective question is this: should it take much effort to open and close the KIPS system when you operate it by rolling the right side actuator cog with your fingers? My moves well, but it just takes a bit to get the system moving.

Thanks! -Matt

Mine was the same way. You could twist it open by hand and it would 'try' to close, but wouldn't. Finally tried replacing that o-ring and found one in an o-ring assortment that worked fine. The operation was smooth as 'butter' after that. Put it in with a little 2stroke premix on it...no problems.

 

[blackduc98]

I also had my cylinder chemically stripped during the replating process. All surfaces were very rough, and had some kind of very fine particles on them which made it feel very coarse, including head and base gasket surfaces, which pissed me off. Anyway, I thoroughly washed the cylinder with soap and water and a brush. I then used a gun cleaning rod with wirebrush attachment to ream all KIPS passages. I also had to do some work with a dremel tool because the left-side kips valve was catching on the edge of resonator passage (which was not the case before replating). BTW, my manual says that the o-ring should be greased as opposed to oiled.

As far as abrupt opening/closing goes: if you look at the left side of the main KIPS rod, you'll notice that it has a cam-like shape. There is a spring-loaded steel ball that presses against this cam shape. As far as I can tell, the purpose of it is to keep the KIPS either completely closed or completely open. In other words, I think "abruptness" is part of this KIPS system by design.

BTW, Karl, how did you determine that your KIPS opens late and abruptly? Did you hook up a tach, remove kips actoator arm cover, and observe the actuator arm?

 

[SSCHOEMAN]

Same with me, left the o-ring out because I couldn't get a part no for it.
It works fine without the o-ring just make sure the advancer-shaft-boot seals tight.

 

[KDX220R]

Who did the replating work?????
My cylinder is due for replating.

 

[blackduc98]

Mine was replated by USChrome. I had some issues with it, but overall not bad. Read the last few posts from the following thread for details and pics:

http://www.dirtrider.net/forums3/showthread.php?p=1043876#post1043876